Here is the skinny: when asking a question be detailed in what the problem is; use patience and answer people's questions regarding your issue politely.
Your topic question implies you know what you are doing, the rest or the thread implies that you are st00pid.
IF YOU KNOW HOW TO USE THE SITE, the two most common reasons why you will have problems posting images are: the server is too busy, which means it cannot except your images, or your images are too large and the server is rejecting them.
Cheers!